Toward a New Era of Companion Animal Longevity and Well-Being

S1https://vetsci.orgIn recent decades, the lives of companion animals have been transformed in ways once unimaginable.Where dogs and cats rarely lived beyond their early teens, it is now increasingly common to see many thrive well into their late teens and even into their twenties.This remarkable extension of lifespan is the fruit of extraordinary advances in diagnostic technologies, therapeutic innovations, nutrition, preventive medicine, and husbandry.It also reflects a profound societal shift: a recognition that pets are not merely animals we care for, but are beloved family members whose health, comfort, and dignity deserve our deepest commitment.As a veterinarian, researcher, and educator, I have witnessed these changes firsthand.Nevertheless, although longer life brings cause for celebration, it also presents new ethical, clinical, and practical challenges.The aging of a companion animal is far more than the passage of time; it is a uniquely personal and complex journey shaped by genetics, environment, nutrition, and the animal's entire life history.Scientific studies-for example, those showing that small and mixed-breed dogs often outlive larger purebred breeds, partially due to differences in biological pathways, such as insulin-like growth factor-1 (IGF-1)-are leading to a new era of precision veterinary medicine, guided by genetic analysis and advanced biomarkers.Similar biological insights are also emerging in feline medicine.Nevertheless, with extended longevity comes a new spectrum of age-related conditions familiar to human medicine: arthritis, organ decline, sensory and cognitive changes, and shifting behavioral patterns.Responding effectively to these challenges requires moving beyond a reactive, disease-focused model of care toward a proactive "life-cycle" approach.This approach prioritizes early detection, prevention, personalized geriatric care plans, and above all, preservation of the quality of life at every stage.This special issue represents the work of a unique collaboration with thirteen internationally renowned leaders in biomedical science, veterinary medicine, gerontology, and longevity research.Together, we have sought to address companion animal aging through three interconnected themes:1.